From a546b17bbaeb12beac4c9aeed56f74a42b18a93a Mon Sep 17 00:00:00 2001 From: "djm@openbsd.org" Date: Wed, 9 Oct 2019 00:02:57 +0000 Subject: [PATCH] upstream: fix integer overflow in XMSS private key parsing. Reported by Adam Zabrocki via SecuriTeam's SSH program. Note that this code is experimental and not compiled by default. ok markus@ OpenBSD-Commit-ID: cd0361896d15e8a1bac495ac583ff065ffca2be1 --- sshkey-xmss.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/sshkey-xmss.c b/sshkey-xmss.c index a29e33f39..9e5f5e475 100644 --- a/sshkey-xmss.c +++ b/sshkey-xmss.c @@ -1,4 +1,4 @@ -/* $OpenBSD: sshkey-xmss.c,v 1.5 2019/06/28 13:35:04 deraadt Exp $ */ +/* $OpenBSD: sshkey-xmss.c,v 1.6 2019/10/09 00:02:57 djm Exp $ */ /* * Copyright (c) 2017 Markus Friedl. All rights reserved. * @@ -977,7 +977,8 @@ sshkey_xmss_decrypt_state(const struct sshkey *k, struct sshbuf *encoded, goto out; } /* check that an appropriate amount of auth data is present */ - if (sshbuf_len(encoded) < encrypted_len + authlen) { + if (sshbuf_len(encoded) < authlen || + sshbuf_len(encoded) - authlen < encrypted_len) { r = SSH_ERR_INVALID_FORMAT; goto out; }